Re: Catalog bloat (again)

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Scott Mead via mobile
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> On Jan 27, 2016, at 22:11, Joshua D. Drake  wrote:
> 
>> On 01/27/2016 03:37 PM, Ivan Voras wrote:
>> 
>> 
>> On 28 January 2016 at 00:13, Bill Moran > > wrote:
>> 
>>    On Wed, 27 Jan 2016 23:54:37 +0100
>>    Ivan Voras > wrote:
>> 
>>    > So, question #1: WTF? How could this happen, on a regularly vacuumed
>>    > system? Shouldn't the space be reused, at least after a VACUUM? The issue
>>    > here is not the absolute existence of the bloat space, it's that it's
>>     > constantly growing for *system* tables.
>> 
>>    With a lot of activity, once a day probably isn't regular enough.
>> 
>> 
>> I sort of see what you are saying. I'm curious, though, what goes wrong
>> with the following list of expectations:
>> 
>> 1. Day-to-day load is approximately the same
>> 2. So, at the end of the first day there will be some amount of bloat
>> 3. Vacuum will mark that space re-usable
>> 4. Within the next day, this space will actually be re-used
>> 5. ... so the bloat won't grow.
>> 
>> Basically, I'm wondering why is it growing after vacuums, not why it
>> exists in the first place?
> 
> If something is causing the autovacuum to be aborted you can have this problem.
It long-running transactions / idle in transaction / prepared xacts

  Have you considered slowing down on temp tables?  Typically, when bleeding, it's good to find the wound and stitch it up instead of just getting more towels....


> 
> JD
> 
> 
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